Telephone service has become virtually ubiquitous throughout the modern world. A person can simply take a telephone off-hook, dial a destination telephone number, and if someone answers the called telephone, the caller can converse with another party anywhere in the world.
Today, however, the public switched telephone network (PSTN) and other telephone networks such as cellular systems provide most telephone services based on number identification of the telephone set or line that each party uses. Services are personalized only to the extent that a party uses the same line and/or instrument. For example, a person typically has one set of service features and billing options available via a telephone on the person's desk at the office, another set of service features and billing options available via the telephone line to their home and perhaps a third set of service features and billing options available via a wireless telephone (e.g. cellular or personal communications service (PCS)). The networks process calls to and from each of these different subscriber telephones based on a separate telephone number.
The proliferation of services causes subscribers inconvenience. For example, circumstances arise in which a subscriber may want a feature or billing option normally associated with one line or instrument, such as the office telephone, when they are in fact using a different line or instrument such as their home or PCS telephone. Also, the extreme increase in demand for telephone services is rapidly exhausting the capacity of the network, particularly in terms of the telephone numbers available under the current numbering plan.
A number of specific solutions have been proposed for individual problems, such as work at home and/or transfer of service to new location(s) as an individual travels. However, each of these solutions is limited or creates its own new problems.
For example, U.S. Pat. No. 4,313,035 to Jordan et al. discloses a method of using an intelligent network to provide a `follow-me` type service through multiple exchanges of the switched telephone network using an AIN type of telephone system architecture. Each subscriber to the locator service has a unique person locator telephone number. To access the system to update data in a service control database, the subscriber dials 0700 and his unique person locator telephone number. The telephone switching office routes the call to a traffic service position system (TSPS) which prompts the caller (e.g. provides an additional dial tone) and receives further digits from the subscriber. The subscriber inputs a three digit access code, indicating the type of update call, and a four digit personal identification number. If calling from the remote station to which the subscriber wishes his calls routed, the local switching office forwards the line identification number of that station to the TSPS. The TSPS forwards the dialed information and the line identification to the data base for updating the particular subscriber's location record. A caller wishing to reach the subscriber dials the subscriber's unique person locator number. A telephone switching office sends the dialed number to the central database. The database retrieves the stored completion number for the called subscriber and forwards that number back to the switching office to complete the call.
The Jordan et al. approach allows calls to follow the subscriber to each new location, but the subscriber must have a unique telephone number for this service. Each station that receives a call also must have a unique telephone number. As such, the Jordan et al. approach actually exacerbates the shortage of telephone numbers. Also, Jordan et al. rely on subscriber input of identification numbers. Subscribers often find this inconvenient, and this technique is often prone to number entry errors.
U.S. Pat. No. 4,899,373 to Lee et al. discloses a system for providing special telephone services to a customer on a personal basis, when the customer is away from his or her home base or office. The personalized services are provided in a multiple exchange office environment, using a central database for feature control. The nationally accessible central database system stores feature data in association with personal identification numbers. A subscriber wishing to use his personalized features while away from home base dials a special code and presents the personal identification number. The exchange transmits a query to the central database, and the corresponding feature data is retrieved from the database. The database forwards the feature data to the exchange, and the exchange stores the received feature data in association with the station from which the request was initiated. Subsequently, the exchange accesses the downloaded feature data to provide telephone service corresponding to the subscriber's personalized telephone features via the station the subscriber is currently operating from. A temporary office arrangement may be established in which the personalized features will be immediately available on incoming and outgoing calls for a period of time specified by the subscriber.
U.S. Pat. No. 5,206,899 to Gupta et al. pertains to a system wherein a subscriber can assign desired characteristics to any "target station" which is an active telephone accessible to a telecommunications network. A call thereafter that originates from the target station can use customized features, such as account code dialing and corporate billing arrangements. Initially, a service profile is created and stored for each subscriber and contains information describing desired features and billing options. The characteristics of a particular target station are changed by an activation process that can be initiated from any location. Automatic number identification (ANI) information associated with the target station is entered into an ANI trigger table in an intelligent switch, and the service profile is loaded into a database. When a call originates from the target station, information in the database is applied to the switch to provide the desired characteristics. An example of one of the features is when an employee of company X wishes to make business related calls from his/her telephone, the call has the characteristics of a call made from the office by a special billing arrangement.
Like Jordan, the Lee et al. and Gupta et al. systems depend on a dialed number entry by the subscriber to activate the service. Also, the Lee et al. and Gupta et al. systems do not provide a simple manner for more than one subscriber to obtain personalized service over the same telephone line. In Lee et al., during the period when the switch stores the roaming subscriber's profile in association with the line, all calls are processed based on that one profile. Similarly, in Gupta et al., while the ANI trigger is set against the line, all outgoing calls cause database access and use of the subscriber's profile in the database. There is no way to fall back on the normal profile for that line unless and until the service for the roaming subscriber is cancelled with respect to that one line.
U.S. Pat. No. 5,247,571 to Kay et al. discloses an Area Wide Centrex service provided by an advanced intelligent telephone network. The service provides centrex features, such as extension dialing, to multiple locations. The Kay et al. Patent also suggests a Work-at-Home feature. This feature allows the home telephone line to selectively operate as a residential line or as a Centrex business line, on a call-by-call basis. For a business call, the user would preface the call with an access indicator to identify a business call. When an outgoing call from the home line lacks the access indicator, the network processes the call as a standard residential call.
The Work-at-Home feature in the Kay et al. system requires only dialing of a code before each outgoing business call. However, the Kay et al. approach requires that the business profile is stored in association with the home line before the subscriber makes the call. The subscriber can use the Centrex billing and service features from the business account only from a home telephone previously associated with the business line. The subscriber can not use the billing and service features from the business account from any randomly selected telephone. Also, from the home line, a person can either use the normal residential profile service or the pre-defined business profile service. There is insufficient flexibility to enable a wider range of services for multiple subscribers through the one line.